合法
héfǎ · HSK 3
legal
⚖️ 合 = combine/fit + 法 = law → fits the law = lawful
合 means to join, fit, or match; 法 means law or method. Something 合法 fits within the law — it conforms to legal rules, hence lawful or rightful. Contrast with 非法 (not + law = illegal).
合 — 乛 (lid/roof) + 口 (mouth)
Originally a pictograph of a lidded vessel — a cover (亼) closing over an opening (口) — giving the core sense of 'come together, join, fit.' From 'fit/match' it extended to 'combine, unite, agree' and to measure-word uses. The reading hé reflects this 'joining' meaning.
法 — water 氵 + go 去
Originally written 灋, combining the water radical 氵 (suggesting a level standard, like water finding its level), the mythical beast 廌 (which judged guilt), and 去 (to remove or banish). The 廌 was later dropped, leaving 法. The core meaning evolved from 'law' or 'standard' to also include 'method' and 'way of doing'.